Device for swinging ships



1950 F. J. VAN DUSEN EIAL 2,531,434

DEVICE FOR SWINGING SHIPS Filed Aug. 8, 1945 INVENTORS Freda/"wk J VanBase/1 BY l l/a/fer A. BMW/(e M -WW AT TORNL'I" Patented Nov. 28, 19502,531,484 DEVICE FOR SWINGING SHIPS Frederick J. Van Dusen and Walter A.Burke, New York, N. Y.

Application August 8, 1945, Serial No. 609,705

1 Claim.

(Granted under the act of March 3, 1883, as amended April 30, 1928; 370O. G. 757) This invention relates to a device for swinging a ship in asmall area.

Iron and steel ships, boats and vessels in general have magneticqualities and their magnetism affects magnetic compasses on board. Thedivergence between correct magnet direction and the direction indicatedon a magnetic compass is known as deviation and varies in amount fordifferent vessels, for different headings of the same vessel, and withlarge changes in latitude.

To eliminate the effect of the ships magnetism insofar as possible andto make a table or chart of the deviation remaining for various headingsof the vessel, several methods are used involving steaming on manydifferent headings. This procedure is known as swinging ship andrequires a large, open body of navigable water, engines in operatingcondition, a calm sea, and good visibility.

This invention presents a device for swinging ship in a small area ofwater, as between piers in a-shipyard and can be used under. almost allconditions of sea and visibility and without the use of the vesselsengines.

Reference is made to copending applications S. N. 609.703 filed August8, 1945, now Pat. #2,466,753 issued April 12, 1949, and S. N. 609,704filed August 8, 1945, now abandoned, which, also disclose and claimdevices for swinging ship in a small area.

An object of this invention is to provide a device for swinging ship ina small area.

Another object is to provide a device for swinging ship without use ofthe ships engines.

Further objects and advantages of this invention, as well as itsconstruction, arrangement and operation, are apparent from the followingdescription and claim in connection with the accompanying drawing.

Fig. 1 is a top plan view of a vessel with the device for swinging shipand the piers with which used.

Fig. 2 is a side elevation of a vessel with the device for swingingship.

Fig. 3 is a fragmentary view of the pintle.

A vessel is designated by the reference numeral l and the piers thatdefine the body of water where the vessel I 8 is to beswung aredesignated by the reference numeral 1 I. I

Welded to the sides of vessel lllare brackets 12 that have inwardly bentportions 13. Attached to portions 13 as by bolts 14 are upwardly andinwardly inclined members l that form with the plate IS a shape in theform of a truncated pyramid strengthened by cross bars I? attached bybolts l8 to the inclined members 15 attached to plate I6 by screws 19.Integral with the plate I6 is a block 28 that has integral therewith apintle.

Rotatably mounted on pintle 2| is a plate 30 maintained in a relativelyfixed position by means 2 of guys 31 attached to plate 30 by rings 32that pass through apertures 33 in plate 30 and that are attached attheir free ends to cleats 34 on piers I I.

In operation, in order to swing ship, movement of the Vessel II! isachieved by guide lines 40 attached to cleats on the vessel 10, or inany other suitable manner. The guide lines 40 are manipulated by hand orotherwise to place the vessel 10 on the heading desired, whereupon thecompass deviation is then determined in the usual manner.

It is to be understood that various modifications and changes can bemade in this invention without departing from the spirit and scopethereof as set forth in the appended claim.

The invention described herein may be manufactured and used by or forthe Government of the United States of America for governmental purposeswithout the payment of any royalties thereon or therefor.

What is claimed is:

In combination with a vessel having brackets on the sides thereof,elongated support members, said members being attached to said brackets,said members extending upwardly and inwardly toward a common point, aplate connecting the upper ends of said members, said members and saidplate forming the general shape of a truncated pyramid, a spacing blockon the upper side of said plate, said block having a pintle, a secondplate, said second plate having a central aperture, said aperturereceiving said pintle and serving as a bearing therefor, guys attachedto said second plate, the free ends of said guys'being attached to landstructures, and guide lines attached to said vessel, wherebymanipulation of said guide lines will permit turning of said vesselabout the axis of said pintle.

FREDERICK J. VAN DUSEN. WALTER A. BURKE.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 26,219 Willis Nov. 22, 1859171,722 Gorringe Jan. 4, 1876 235,669 Colony Dec. 21, 1880 600,891Schausten Mar. 22, 1898 1,008.564 Schmidt Nov. 14, 1911 1,086,742 WrightFeb. 10, 1914 1,798,851 Roane Mar. 31, 1931 1,852,338 Shaffer Apr. 5,1932 2,312,567 Lyon Mar. 2, 1.943

FOREIGN PATENTS Number Country Date 698,461 France Nov. 18, 1930

